TWI334049B - Driving device for backlight assembly and liquid crystal display device having the same - Google Patents

Description

1^34049 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a driving device for a backlight module of a liquid crystal display. [Prior Art] The Planar Display _ sub includes electric (four) display panels (PDPs), field emission displays (10) (FEDs), and liquid crystal displays (LCDs). Flat panel display

Type display and light reduction shirt. (4) First launch ☆ 1 non-panel and field emission display is coming - the emission type is TFi, and the liquid crystal display is light receiving type... 曰 ' °. It can't be an image of an external light source because it can't shine on its own. Therefore, the liquid display requires a backlight module to emit light. /日曰” ‘,, the backlight module's general requirements include high brightness, high efficiency, brightness hook, long life, external reliance, heavy balance and low cost.

U correction year 曰" ___#i charging is a lamp with a backlight module with the lamp and long life, so it reduces its power. PC monitors or TVs are also equipped with high-brightness backlights. Module - backlight module (4) - lamp or a plurality of health pipes as wire. The backlight mode is divided into side light type and direct type. In the side light type backlight module, the light tube is located at the side of the liquid crystal panel and is guided by light. (4) Leading the light from the lamp (4) to the liquid crystal panel. The lamp is located at the side or the plurality of health pipes are located on different sides of the liquid crystal panel, for example, the left side and the right side. Similarly, a plurality of lamps can be located in the liquid crystal panel. At the same time, in the direct type of back, a plurality of tubes are located at a predetermined distance from the liquid crystal panel, so that they directly illuminate the liquid crystal panel. In the two backlight modules, 1334049 'U is corrected to Widely applied. The first picture is the straight cold intent in the prior art backlight module, the first exhaust first 峨 峨 冷 冷 cold cathode tr reference 1A, straight cold cathode camp light tube and its two _ electrodes (5). Face tube u_extension)_ tube 1 Both ends of the tube 1. A traverse of her _, 3 is provided to a predetermined 4 at the end of the pole 2, 3 is located inside the face tube 1. Therefore, the predetermined electric strict, JI: = tube ^ space 'causes the discharge therein. This straight cold The cathode; the light = the high __pan ___ with the number f is applied by the well to achieve a large-size liquid crystal panel. However, the direct-type backlight wedge requires a wide-panel panel with two f-type back-front modules. By the size of her (four) large size LCD, the size is huge. In order to solve the complexity of the material m and the driving circuit, the gentry " shouted different attempts to change the production. For example, U-shaped hybrid poles and 2-character cathode fluorescent lamps refer to Figure 1B, U-shaped cold cathode fluorescent lamps 1 and electrodes 8 and 9. The glass tube part eight 5 Ze 6/# has a glass wall tube part 5 and 6 parts eight W and 6 are paired in the whole. Each-face tube two:; = and - points 7. _ and two therefore '-(four) cold cathode fluorescent lamp" should be in two wire cold cathode camplights 99. 99. ~nifsL\ 0 supplementary quantity domain shaped cold cathode camp = tube 1/2.? in phase (10) _ The wire cold cathode lamp requires two driving voltages and a U-shaped cold cathode winding μ a lamp to require a crane, and the lamp driving circuit can be reduced by the cost of the lamp. The U-shaped external fluorescent tube is driven in a floating manner. 7 π Figure 2 is a schematic diagram of the backlight module driving device with a dome-shaped lamp shown in Figure 1. Referring to Figure 2, the backlight module driving device Including - controller η, output pulse width modulation (PWM) to control the signal, a power transistor ^, convert the applied DC voltage to DC square wave voltage to make it difficult to make money, - resonance reverse thief 15 'convert DC The square wave voltage becomes an alternating sine wave voltage. Although there is only one common reducer in the second towel, two resonant inverters are required to supply an alternating voltage to each of the electrodes 8 and 9 at the U-shaped tube 17. A first alternating voltage and a second alternating voltage are applied to the electrodes 8 and 9, respectively. Here, the first The phase of the flow voltage is opposite to the phase of the second alternating voltage. Therefore, there is a weak voltage (ideally ov) in the bent portion 7 of the U-shaped lamp tube. The glass tube portions 5 and 6 have the same length and the first alternating voltage. The phase is always opposite to the phase of the second alternating voltage between the electrodes and at the curved portion 7. Therefore, the first alternating voltage is cancelled by the second alternating voltage at the curved portion 7. This is called a floating type drive. The first and second alternating voltages are supplied to the electrodes 8 and 9 respectively. The glass tube portions 5 and 6 can emit light of the same brightness. Since the induced state and the capacitor cause the resonant reverse 15 to have an impedance. Similarly, the f W correction 2 The lamp tube 17 itself has a mother-resistance of the resistance 15 and the U-shaped lamp tube 17. The impedance is different due to an external factor (such as noise). Therefore, the compound female g-port is divided into 5 and 6, and has different impedances. In addition to the curved portion 7, the damage of the first and second alternating voltages is caused by the resistance in the broken portion of the broken tube. In the first - #6 « mutually offset portions do not produce light. Similarly, when the first And second exchange; electricity = tube part 5 When the discharge is generated, the current flows through the breakage tube portion 2 and the current varies according to the impedance. Therefore, due to the impedance difference, the respective tube currents passing through the broken glass portions 5 and 6 become different from each other. In the δ battalion part, there is a high ancient household: and the right 钤丨 total dry & 8g package " 丨L's slashing knives, there are ^ degrees and smaller official current _ tube part which leads to the brightness of the code from /, (10) redundancy. Detecting the electrical characteristics (eg, voltage, current, and impedance) of the U-shaped tube 17 - 兀 (not shown) is connected between the resonant inverter 15* U-shaped tube nozzle Thus: the electrical characteristics detected by the 疋 are supplied to the controller U, thereby entering the corresponding control operation. Since the horse is connected 7L early between the resonant inverter 15 and the U-shaped light booth h, 17 The exact impedance of the u-shaped lamp 17 cannot be detected. When the glass tube portion is accurately detected, m and the second AC cake are controlled. However, the difference in impedance between the front portion of the wedding tube portions 5 and 6 of the u-shaped tube π is accurately detected. Large-size LCD panels require a long U-shaped lamp tube 17. When the U-shaped lamp tube 17 is long, the 苐- and the second AC voltage drop due to the intrinsic impedance of the glass tubes 5 and 6. Appears in the curved portion 7 - the large face is lowered. When the end of the replacement portion has a date of 1334049, the curved portion 7 has a low unevenness. [Content of the Invention]

W V - Red Top Problem The present invention provides a lamp and a backlight having the lamp switch, thereby substantially eliminating one or more problems caused by the (4) or disadvantage of the previous. SUMMARY OF THE INVENTION It is an object of the present invention to provide a driving device for a backlight module and a backlight module having (4) lamps to provide stable electrical characteristics. The advantages, objects, and features of the present invention will be described later on the side of the towel. Subsequent inspections with ordinary techniques will be more apparent, or may be made from the practice of the present invention. The present invention and other advantages can be recognized or obtained by the structure indicated by the specification and the scope of the patent application and the towel. According to the present invention, the above objects and other advantages are provided, and the detailed description herein provides a lamp tube including first and second glass portions of light emission, the respective ends of the first and second glass tubes being bent and completely connected to each other; And a second electrode is formed at each of the other ends of the first and second glass tubes; and the third electrode is formed at a curved portion of the first and second glass tube portions. A backlight module driving device, wherein the device switching unit 'corresponds to a control signal, in another aspect of the present invention, provides a controller having a control signal; an output-DC square wave voltage; and a reverse conversion DC side Frequency (4) AC voltage; and a lamp corresponding to the AC voltage to emit light, the lamp includes: first and second glass tube portions having a twist from one end and being completely connected to each other; first and third (3) 4049 stagnation On the 4th and 7th of the year, the electrodes are formed at the other ends of the first and second glass tube portions respectively; and the second electrode is formed at the curved portion of the first and second glass tube portions, wherein the third electrode Ground. In another aspect of the present invention, a backlight module driving device is provided, which has a controller-output-control signal; a conversion unit corresponding to the control of the six-dimensional transmission Converting the DC square wave to a voltage of *, and a lamp corresponding to the alternating voltage to emit light, the lamp comprises: first and second glass tube portions having respective ends bent and completely connected to each other; An electrode is formed at each of the other ends of the first and second glass tube portions, respectively; and - a third electrode is formed at a curved portion of the first and second glass tube portions, and the @electrode is derived from the third electrode. In the 1s = _ _ other _ aspect, a f-light module is provided, and the controller 'output-control signal; the conversion unit corresponds to the control. , two out ~ DC square wave voltage; - heart 'work AC voltage · such as 4 change to the flow square tree voltage has become a separate lamp, corresponding to the AC county light, the lamp includes: : two: curved and complete each other a first and second glass tube portion connected; a first and a second portion at the other end of the first and second breaks; and a curved portion provided with the first and the third: Give the third electrode. In addition, the AC voltage of the opposite phase of the IL voltage is in the other aspect of the present invention, and the liquid crystal panel with the image is not displayed. This [_二.g 卞 卞 includes: - (four). . Board, this unit state, output a control signal; - έ _ signal rotation - DC square wave voltage; - reverse (four): straight = 'corresponding to control AC voltage; and - ^ like anti-奂 DC square wave voltage It has its own-end-curve: two-phase voltage illuminating, and the lamp tube includes: a portion having a (m) m-age portion; a first=:? is formed at the other end of each of the first and second glass tube portions; and the shaft is formed In the first and second sacrificial parts, the third one in the other aspect of the present, provides a liquid chain _q q /, /, like the image of the liquid crystal panel package J π #光模_A single ball is supplied to the LCD panel, this unit poem, φ · - control · output - control signal; - conversion, corresponding to the control letter = hemp - DC square wave voltage; - reverse conversion DC square wave The voltage becomes a 'and-light tube, which corresponds to the alternating voltage to emit light. 2: The first and second glass have been bent and completely connected to each other: -: Dad knife is formed in the first and third glass tubes Part of each of the other ends; and the bending characteristics of the first electrode axis at the first portion are detected by the (four) 4 poles. In another aspect of the invention of the rtf of the lamp 4, a liquid crystal panel having a display image is provided - the back wire canister unit supplies light to the liquid crystal panel, and the unit mirror: has a controller output - a control signal; - The conversion unit corresponds to the control signal outgoing-DC square wave voltage; an inverter converts the DC square wave voltage to the AC $ correction supplement 99, 4.- Voltage ·》必狄--- _ Ίη\ Illuminating at an alternating voltage, the lamp includes: first and second glass tube portions having a first end material and being completely connected to each other; and second and third portions are respectively formed in the first and second glass tube portions The other end: and one has: ° the curved portion of the first and second broken glass tubes, wherein the provided: ♦ is provided to the younger brother - the second electrode is the opposite phase of the alternating current to the first -% It should be understood that the general description and the following detailed description of the present invention are examples and two explanations, and the purpose is to explain the three types of the present invention. [Basic method] | About the 4 call and implementation, the best example of the best example is the phase = where under what circumstances, the reference number of the group represents the same or the year 3 _ based The invention _ implementation of the backlight mode _ - cold cathode glory ^. Referring to Fig. 3, the cold cathode fluorescent lamp tube includes a tube portion 31*32 having a length of money, the respective ends of which are bent to the connecting portion f, and the second electrodes 34 and % are respectively formed in the first sum. = The respective other end-to-end rides of the slope-increasing portion are exposed to the inside of the other end, and the third electrode 36 is formed at the joint portion of the first and second glass tube portions. 6 The cold cathode fluorescent tube is a modified u-shaped tube 47 (see the figure U to the fourth section). The U-shaped tube of the cutting technique further includes a third electrode 36 located at the connecting portion 33. 12

The year of the month and the correction of the first brother and the second broken glass are made of glass. The predetermined length can be 〜 ~ a transparent break cup with a predetermined length, the size of the _ τ plate is proportional. That is, the liquid removal day panel is small and can form a short first and second broken liquid, in addition, when the liquid crystal surface; + gentleman-Γ, sickle) 1 and 〇 2 on the c Tian Xin 曰曰Big 4 can form long and 32. Since the nth and the second glass portions 31 are not in the same position as the first and second electrodes 34 and 3, they have the same horizontal position. The first H + shot portions 31 and 32 are filled with the surface for releasing the - and the second glass tube portions 31 and 3), such as and applied to the first stable, fluorescent material is not applied to the first and second materials. . In order to make the powers connect to each other flat. 1 (four) and the second tube portion first to third electrodes 34 to 36 may be other. The first and the first - the Imperial 3' ', the clothing, the ruthenium, the silver, the copper, the poles 34 and 35 are needle-shaped, and the deputy is to the first and the flute two glass tube part 31 and the brother and the Fudu. Conversely, the third electrode % is coated in the first and second-glass portions 31 and 32, or the outer periphery of the joint is coated with 1 electric (four) _ ^ attached to a gold depending on the cold cathode fluorescent tube Connected to the controller - #1 - 1 pole 36 can be grounded, you can smash the pole of the first light camp to the - power unit to make H m ' or can be electrically connected. The first HP secret surface is supplied in a single shape: snow electrodes 34 and 35. (7) Death Supply '·· 口乐一和苐二 Figure 4 is a diagram of the backlight module driving device according to the present invention, which is intended to be modified. Refer to the ^ diagram, including the wheel off-out 1 (PWM) 氺 岳 岳 岳 出 脉冲 脉冲 足 足 足 足 足 足 足 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; A power transistor =: an alternating current sine wave voltage - a resonant inverter 45, and a hair: two = § 纟 U-shaped tube 47 also has a grounded third electrode 36. And the controller 41 rotates a pulse width modulation (pWM)

The gate, while the external DC is supplied to the power transistor μ - and :. The + transistor 43 is cycled == according to the pulse width modulation control signal, and is converted into a DC J having a plurality of pulses according to the DC voltage = Resonant Inverter 45_Resonator and _Variation_. The resonator includes a resistor-inductor and a capacitor. The resonator converts the DC square wave into a red sinusoidal voltage, which is sent by Wei Weilin. 7 In order to simplify the device, there is only one resonator, but two, and a vibrator is required to provide the alternating current in the U-shaped tube 47 (four) - and the second electrodes % and 35. - The first - and the second alternating current and the second alternating current are applied to the first and second alternating currents and 35. In the prior art, the phase of the first alternating voltage is subtracted from the phase of the second alternating voltage. Since there is a grounded third electrode 36 at the connecting portion 33, the phase of the first alternating current voltage may be opposite to the phase of the second alternating voltage 14 1334049 or the same in the embodiment of the present invention. In the u-shaped lamp tube 47, an electrode 34 and an electrode 34 and 35 are formed at the end of the first and second glass, respectively, and are connected to each other. And a connecting portion of the second glass tube portions 31 and 32]. The first - Μ and 35 are connected to the resonance reversal ^. Therefore, the second AC voltage that is excited against her is turned over at the first and second electrodes Μ # %. Since the third electrode) 6 is grounded, the phase of the first voltage may be opposite or the same as the phase of the second revolution. That is, the phase of the 'first voltage' and the phase of the second voltage may be opposite or the same. Conversely, the curved portion of the floating U-shaped bulb according to the prior art is not grounded. Therefore, the first and second voltages with opposite phases may be different from the other materials of the glass tube due to the different Sister's resistance. Therefore, the brightness of other parts may be undesirably lowered. Similarly, due to electrical characteristics, the electrical characteristics of the prior art bulbs were not detected as detected between the resonant inverter and the U-tube. Since the third cups 3 to 36 of the U-shaped bulb 47 are grounded, there is always a ground voltage at the connecting portion 33. Therefore, the brightness of the first and second @1 埂(5) words 31 and 32 becomes uniform, and stable electrical characteristics can be obtained. The inflammation between the I and the third electrode 36 can be used as a horse-maize test point. Therefore, the internal impedance of the first and second glass tube portions 31 and 32 can be maintained. Therefore, it is possible to avoid the difference in the current through the first tube. spear. The second glass fringe portion of Fig. 5 is a supplement/intention of the backlight module driving device according to the second embodiment of the present invention. In the driving device according to the second embodiment of the present invention, the three electrodes 36 are electrically connected to the controller 41 as shown in Fig. 5. The driving device shown in Fig. 4 of the Gentleman ▲ g 47 is the same, and therefore the third electrode 36 of the U-shaped lamp tube 47 is omitted for the sake of simplicity, the structure and connection of the core and the reference to Fig. 5. Connected, the U-shaped lamp 47 electrical characteristics (for example, the impedance of the electric two ☆ 4! electrical connecting portions 31 and 32) can be connected to the u-shaped lamp at the connecting portion 33 via the ^2 Tube 47~ "come to be smashed" Some electric special micro-dirty employment. Electric power inch. But therefore, the U-type heart resistance I""&&&&&&" accurate electric The special coffee (4) her body ^ brother 6 is a backlight according to the third embodiment of the present invention. Referring to the sixth and the same, the unsatisfactory 34 and 35 brothers and brothers and two brothers AC voltages are respectively supplied to the first sum. The second electric third ion third alternating voltage is supplied to the third electrode 36. To achieve the first and the second, the resonant reverse direction 11 45. At the same time, the same phase and the first voltage are respectively supplied to The first and second electrodes 34 and 35 have a voltage of 36. The third alternating voltage of the opposite phase of a parent current voltage is supplied to the third electrode for the wide-screen liquid crystal panel 'the lamp tube becomes longer. When the AC voltage is lowered ^ S 1 end's length through the long lamp will make the supplied AC _α this 'provide to the other end of the long tube exchange The voltage is greatly reduced, and the brightness of the s-end is greatly reduced. The third embodiment solves the above problem. Also, 16 years θ, that is, due to the provision of n-dead #弟一父, voltage opposite phase The first time: the surrender of the private fort to the connection part 3 is increased. The younger H6' is therefore bright at the connecting part 33 (EE=: the lamp tube is as described in the embodiment of the invention, the outer electrode is the first example of the lamp) ^ Tree ah (4) Heart (4) Bribe light tube umbrella Γ At the end of the tube (four) points. Fluorescence in the outer electrode ^

The electrode can be secreted into any part between the two end portions of the end W = of the fresh portion. When having a formation:: tube

The outer electrode fluorescent lamp is simply bent into a U-shaped shape, and the present invention can also be applied to an external electrode camp light tube. Second, in the shape of the lamp as above, the present invention can also be used in the 2-word miscellaneous tube. The H-tubes U are as above, and in the embodiments of the present invention, each of them is resistant to different wire-tear wheels. = Γ 获 获 获 获 获 获 获 获 获Similarly, use the lamp at the bend to age (10), but you can give it to the lamp. ^ Even in a widescreen display, you can get a bright heart: two electrodes. Therefore, although the present invention has been disclosed in the foregoing preferred embodiments, the invention is not limited to the invention, and is not limited to the invention;: t is used to limit: when a little change and retouching can be made, the present invention The patent protection is subject to the definition of the patent application scope attached to this book. Μ 须 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 133 The figure is a schematic diagram of a backlight module driving device with a U-shaped lamp tube shown in FIG. 1B; FIG. 3 is a schematic diagram of a cold cathode fluorescent lamp tube of a backlight module according to an embodiment of the invention; 4 is a schematic diagram of a backlight module driving device according to a first embodiment of the present invention, and FIG. 5 is a schematic diagram of a backlight module driving device according to a second embodiment of the present invention, and FIG. 6 is a diagram according to the present invention. A schematic diagram of a backlight module driving device of a third embodiment. [Main component symbol description] 1 glass tube 2 electrode 3 electrode 5 glass tube part 6 glass tube part 7 curved part 8 electrode 18 1334049 with 4. -3⁄4 correction year and month supplement • 9 electrode '11 controller 13 power transistor 15 resonance Inverter 17 U-shaped lamp tube 31 first glass tube portion 32 second glass tube portion φ 33 connection portion 34 first electrode 35 second electrode 3 6 second electrode 41 controller 43 power transistor 45 resonance inverter φ 47 U-shaped tube

Claims (1)

: ^^月7曰Revised - backlight module, device, Baocai: L~~~J Inverter - lamp, = view DC square output becomes - AC voltage; and should be illuminated by the parental voltage, The lamp further comprises: χ - controller, wheel control signal; π early π, tangential control money output _ DC square wave voltage; $ off-tube portion; at the first - and second electrode: /. The respective impedances of the first and second glass tube portions, each of which is bent at the respective ends, and which are completely connected to each other, and the second and the other ends of the second tube respectively form a different impedance between the second tube portions. Five sighs are used as reference points to compensate for the first and second. 2. The device heart described in the scope of patent application 苐1 and the opposite phase of the @___^2 are described in the following paragraphs: And the first, the exchange series are respectively provided to the fourth phase of the same phase, such as the z-shaped lamp of the claim. <Clothing, wherein the tube is a dome-shaped tube 5. As in the patent application, the tube (coffee) or the external electrode fluorescent lamp == followed by the cold cathode: 20 丄JJ 丄JJ ^ 2曰 replacement page The backlight module driving device comprises: a controller outputting a control signal; - a fresh element corresponding to the control money (four) - a DC square wave voltage; - an inverter "converting the DC square wave voltage into a DC voltage" And a light tube corresponding to the alternating voltage to emit light, the light tube further comprises: one and eight ends having a "end bending" and a complete connection with each other (four) - and a second surface tube - a glass branch, each other, in the a 'curved portion of the second glass tube portion is formed - a: a strip, wherein the electrical characteristics of the tube are derived via the third electrode _; % - wherein the miscellaneous device corresponds to the measured electrical characteristics to control the lue 'Where the electrical characteristics include the voltage, current and foot of the lamp. 7. See paragraph 6 of the patent application. Z-shaped tube. Shaped tube or 8. The device of claim 6, wherein the tube is a tube (CCFL) 4 electrode fluorescent tube (EEFL). 9. A backlight module driving device, comprising: - a controller 'wheeling out - a control signal; a conversion unit, an inverter ' ^ should be in the control signal output - DC square wave electricity; Wu the DC square wave The voltage becomes -DC voltage; and 21 1334049, July 2, 1999, replaces a lamp, corresponding to the AC voltage to emit light, the lamp further includes: first and second having respective ends bent and completely connected to each other a glass tube portion; forming first and second electrodes respectively at respective other ends of the first and second glass tube portions; and forming a third electrode in the curved portion of the first and second glass tube portions, wherein the provided and provided An alternating voltage of an opposite phase to the alternating voltage of the first and second electrodes is applied to the third electrode. 10. The device of claim 9, wherein the tube is a U-shaped tube or a Z-shaped tube. 11. The device of claim 9, wherein the tube is a cold cathode fluorescent tube (CCFL) or an outer electrode fluorescent tube (EEFL). 12. A liquid crystal display comprising: a liquid crystal display panel for displaying an image; and a backlight module driving unit for providing light to the liquid crystal panel, the unit further comprising: a controller for outputting a control signal; Unit, corresponding to the control signal output, the current square wave voltage; 22 1334049 Replaced on July 2, 1999 An inverter and a converter for converting the DC square wave voltage corresponding to the alternating voltage to emit light, the lamp tube further comprising: a first glass tube portion having respective ends bent and completely connected to each other; - and the respective other ends of the second glass tube portion are respectively formed into the first and second electrodes; and a third electrode is formed in the curved portion of the first and second glass tube portions, wherein the third electrode is grounded, and Set to the reference point to compensate for the different impedance between the first and second glass tube sections. 13. A liquid crystal display comprising: a liquid crystal display panel for displaying an image; and a backlight module driving unit for providing light to the liquid crystal panel, the unit further comprising: a controller for outputting a control signal; The conversion unit works out - DC square wave voltage, . L converts the DC square wave into the AC voltage f and - the lamp officer 'corresponds to the turbulent voltage to illuminate, 23 the tube H tree: _ section respective - end bending And first and first glass battalions partially connected to each other; one end is formed in each of the first and second glass tube portions, respectively, and the first and second electrodes are formed; and the curved portions are formed in the second and second glass tube portions A third electrode, 1 oblique rattan and electrical characteristics are detected via the third electrode, wherein the control Η贞 electrical characteristic controls the lamp, wherein the voltage, current and impedance of the lamp are present. A liquid crystal display comprising: a liquid crystal display panel for displaying an image; and an optical module driving unit for providing light to the liquid crystal panel, the unit further comprising a controller for outputting a control signal; The conversion unit outputs a square wave voltage corresponding to the control signal; an inverter converts the DC square wave voltage into an AC voltage; and a lamp corresponding to the AC voltage to emit light, the lamp further includes: 24 1334049 July 2 曰 曰 replacement page having first and second glass tube portions each bent at one end and completely connected to each other; forming first and second electrodes respectively at respective other ends of the first and second glass tube portions; And forming a third electrode in the curved portion of the first and second glass tube portions, wherein an alternating voltage having an opposite phase to the alternating voltage supplied to the first and second electrodes is supplied to the third electrode.